Implement asset upload API and utility functions

- Add Asset and CardLayer model updates
- Create asset upload API endpoints
- Add AssetUploadDialog component
- Create card layout algorithms
- Implement symmetry generation utils
- Add template configurations

backend/apps/projects/views.py

@@ -1,8 +1,12 @@
 from rest_framework.decorators import api_view
 from rest_framework.response import Response
 from rest_framework import status
-from .models import Project
-from .serializers import ProjectSerializer, ProjectDetailSerializer
+from django.core.files.storage import default_storage
+from django.conf import settings
+from PIL import Image
+import os
+from .models import Project, Asset
+from .serializers import ProjectSerializer, ProjectDetailSerializer, AssetSerializer
 
 
 @api_view(['GET', 'POST'])
@@ -42,4 +46,81 @@ def project_detail(request, pk):
 
     elif request.method == 'DELETE':
         project.delete()
+        return Response(status=status.HTTP_204_NO_CONTENT)
+
+
+@api_view(['GET', 'POST'])
+def asset_list(request, project_pk):
+    """获取项目素材列表或上传新素材"""
+    try:
+        project = Project.objects.get(pk=project_pk)
+    except Project.DoesNotExist:
+        return Response({'error': 'Project not found'}, status=status.HTTP_404_NOT_FOUND)
+
+    if request.method == 'GET':
+        assets = project.assets.all()
+        serializer = AssetSerializer(assets, many=True)
+        return Response(serializer.data)
+
+    elif request.method == 'POST':
+        if 'file' not in request.FILES:
+            return Response({'error': 'No file provided'}, status=status.HTTP_400_BAD_REQUEST)
+
+        file = request.FILES['file']
+        asset_type = request.POST.get('asset_type', 'unknown')
+        asset_key = request.POST.get('asset_key', 'unknown')
+
+        # 创建项目素材目录
+        project_media_dir = os.path.join('projects', str(project.id), asset_type)
+        full_dir = os.path.join(settings.MEDIA_ROOT, project_media_dir)
+        os.makedirs(full_dir, exist_ok=True)
+
+        # 保存文件
+        file_name = f"{asset_key}_{file.name}"
+        file_path = os.path.join(project_media_dir, file_name)
+        saved_path = default_storage.save(file_path, file)
+
+        # 获取图片尺寸
+        try:
+            img = Image.open(file)
+            width, height = img.size
+        except:
+            width, height = None, None
+
+        # 创建Asset记录
+        asset = Asset.objects.create(
+            project=project,
+            asset_type=asset_type,
+            asset_key=asset_key,
+            file_path=saved_path,
+            file_name=file_name,
+            width=width,
+            height=height
+        )
+
+        serializer = AssetSerializer(asset)
+        return Response(serializer.data, status=status.HTTP_201_CREATED)
+
+
+@api_view(['GET', 'DELETE'])
+def asset_detail(request, project_pk, asset_pk):
+    """获取或删除单个素材"""
+    try:
+        project = Project.objects.get(pk=project_pk)
+        asset = project.assets.get(pk=asset_pk)
+    except (Project.DoesNotExist, Asset.DoesNotExist):
+        return Response({'error': 'Asset not found'}, status=status.HTTP_404_NOT_FOUND)
+
+    if request.method == 'GET':
+        serializer = AssetSerializer(asset)
+        return Response(serializer.data)
+
+    elif request.method == 'DELETE':
+        # 删除文件
+        if asset.file_path:
+            file_full_path = os.path.join(settings.MEDIA_ROOT, asset.file_path)
+            if os.path.exists(file_full_path):
+                os.remove(file_full_path)
+
+        asset.delete()
         return Response(status=status.HTTP_204_NO_CONTENT)